Place rubber pads underneath the legs of your furniture. The rubber immobilizes the furniture and reduces movement to protect the floor. Rubber pads are inexpensive and available at a hardware store or grocery store.
Cut out flannel fabric squares. Set the squares underneath the furniture to prevent the furniture from rolling against the floor.
Purchase carpet tiles for your hardwood floor. Carpeted floor tiles are individual pieces of carpet with a rubber backing that protect your hardwood floor and eliminate furniture movement. Alternatively, use an area rug with a rubber mat underneath the furniture to stop slippage.